The present invention generally relates to packaging methods for electronic circuit components, particularly to improved pockets for packaging methods for electronic circuit components, and specifically to improved pockets for packaging methods for electronic circuit components for aiding in the non-contacting, electro-optical vision inspection of electronic circuit components located in the pockets.
A common packaging method for electronic circuit components such as microchips is placement into pockets located at precise intervals on a carrier medium. Specifically, such pockets could be arranged in arrays of rows and columns in trays and, especially common for small resistors, capacitors, and memory boards for surface mount assembly of circuit boards, could be arranged in continuous columns in carrier tapes.
As part of the manufacture of electronic circuit components, the leads of the electronic circuit components are inspected for improper bends, out of specification configurations, and like abnormalities. This inspection can occur while the electronic circuit components have been removed from the pocket, but this is a time consuming and relatively expensive procedure. This inspection can also occur while the electronic circuit components are in the pocket but before the pockets are covered in a manner to avoid accidental falling of the electronic circuit components from the pocket. Such in the pocket inspection generally utilizes non-contacting, electro-optical vision systems having frame grabbers and clever algorithms to compare the electronic circuit components in the pocket with a desired standard.
Although easier and less expensive to perform than out of the pocket inspection, in the pocket inspection results in the indication of many false rejections which require extra time for human inspection and override. Specifically, due to their placement out of center in the pocket or due to their shifting in the pocket due to movement of the pocket, the leads of the electronic circuit components can be located closely adjacent or abutting with the side walls of the pocket. Such leads can cause a reflection on the side walls which can not be differentiated from the actual lead by the electro-optical vision system and would then be considered as extra long leads. Since long leads would be a flaw in the manufacture of electronic circuit components, the inspection would indicate a rejection which typically stops operation until manually overridden by the operator. The manufacturers of electro-optical vision inspection systems have attempted to overcome this problem of the false indication of improper lead problems by various approaches such as but not limited to using point source lighting, using diffuse lighting, using polarizing or color filters, and the like. However, such attempts by manufacturers of electro-optical vision inspection systems have not been successful in overcoming this problem of the false indication of improper lead problems.
Thus, a need continues to exist in the field of in the pocket inspection of electronic circuit components for eliminating the false indication of lead problems as the result of the positioning of the leads in close vicinity to the side wall of the carrier pocket.